Controller for gas-heated apparatus



Aug. 9, 1938. K. FIEDLER ET AL 2,126,373

CONTROLLER FOR GAS HEATED APPARATUS 7 Filed Feb. 5, 1954 2 Sheets-Sheet 1 Aug, 9, 1938. K. FIEDLER ET AL 2,125,378

CONTROLLER FOR GAS HEATED APPARATUS Filed Fb. 5, 1954 2 Sheets-Sheet 2 1 Win! a9 "\31 vi i ag\ Patented Aug. 9, 1938" UNITED STATES CONTROLLER FOR GAS-HEATED ArrAnA'rUs Kurt Fiedlcr, Stuttgart, and Georg Hegwein and Otto Merten, Dessau, and Friedrich Wilhelm Stockmeyer, Stuttgart, Germany, asslgnors to Junkers & 00. G. m; b.- 11., Dessau, Germany Application February 5, 1934, Seriai No. teas-19 ,4,

, In Germany February 8, 1933 18 Claims.

I The present invention relates to controllers for gas-heated apparatus, such as liquid-heaters, airheaters or the like, in which the supply of gas is dependent, on the one hand, on variations in 5 gas pressure or flow and, on the other hand, on working conditions of the medium to be heated for instance liquid or air pressure, or tempera ture. The variations in gas pressure may be produced by fluctuations in pressure in the gassupply pipe or passage; they may also be produced in; an auxiliary passage by so-called controlling valves, which in their turn are controlled by sensitive adjusting devices, for example by the 1 heat of a pilot-flame. J

13 Controlling devices are already known in which the valves influenced by the working conditions of the medium to be heated also act on a current "of control gas flowing, for instance, in a branch gas passage, the pressure variations in which 0 operate the so-called main gas valve. In thiscase, when the gas pressure conditions are insuiiicient, suiflcient 'adjusting forces are not always available for operating the main gas valve, whilst the adjusting devices to be oper- 26 ated by the working conditions of the gas apparatus may easily be arranged for the operation of even strongly loaded valves having great closing force. Now a second -valve, for example, a safety valve, 30 influenced by alterations ingas pressure has already been arranged behind a gas valve controlled by the flow or temperature of the mediumito be heated. In th s case, it is found by experience that the first-named valve is frequently operated, whilst a safety valve controlled,

say, by the pilot flame through a current of controlling gas only very se om comes into operation,namely,' on the xtinction of the pilot flame. The danger therefore exists that this 40 safety valve may seize during the-long periods of rest, and then fail at the very time when it should, with certainty, intervene in the controlling operation. If, on the other hand, this second valve serves as a gas pressure or gas consumption regui5 lator, the passage of gas does not always coincide with the working requirements of the apparatus, but is controlled exclusively corresponding to the properties of the adjusting device in question, for instance a diaphragm or float disc 50 surface or valve load, whereby the adjusted heating capacity does not always correspond to the actual working conditions.

The object of the present invention is to remove these-drawbackss, to permit a far better i5 adafitatipnof the gas supply to the working conditions of the apparatus and to ensure, even when employing safety valves which rarely come into action, increased security for permanent reliable working.

The invention consists in the fact that the controlling arrangementoperated by the gas pressure is influenced in such a way by the device controlled by the workingconditions of the gas apparatus that it must follow its closing movements, but under the influence of the gas presno sure variations acting on its adjusting member,

, for instance a diaphragm or float disc, can perform independent control movements.

This mutual influencing of the two arrange-- ments can be eflected by mechanical-coupling w 'ing conditions of the gas appliance; the gas current to the burner in this case undertakes the mutual influencing of the two regulating devices in the desired direction of adjustment and thus 25 replaces mechanical coupling members.

Several examples of construction of the invention are shown in the accompanying drawings, in which:-

Figure 1 shows a gas-heated apparatus having so a gaspressure controller the valve of which is also influenced by the flow of the medium to be heated.

Figure 2 shows an apparatus having a gas quantity controller the load on which constantly 35 varies with the quantity of the medium to be heated.

Figure 3 shows a heating appliance controlled. by a thermostat, whose heat-sensitivemember acts on a safety valve which is controlled by the 40 variations in pressure occurring in an auxiliary pipe.

Figure 4' shows a controlling arrangement in which a control device operated by the flow of the medium to be heated controls the cross section at which the fall in pressure occurs for controlling a. gas-pressure control device constructed as a gas quantity regulator.

Figure 5 shows a construction in which the degree to which the gas pressurei'control device is influenced by the control device of the apparatus can be altered by an externally operated adiustin member.

In all the controlling arrangements illustrated, an adjusting member (gas pressure control device) A controlled by diiierences in gas pressure, and a control device B, dependent, for instance. on the pressure or the quantity of the medium to be heated, on a working temperature or other working condition, are present, and Jointly influence the supply of gas to the burner C.

In the construction shown in Figure l, A is a gas-pressure controller, controlled by the consumption pressure and having a diaphragm l and valve 2. This valve is under the influence 01' a push-rod 4 connected with the diaphragm 3 of the control device B. The pressure chambers I and 8 of the casing 3 separated by the diaphragm 3 are connected by pressure relief pipes in and II to the parts l3 and I4, connected together by a contracted part |2 of the cold water pipe leading to the heater D. When no water is taken from the heater, the same pressure prevails in the two pressure chambers I and 3, the diaphragm 3 with the push-rod 4 is pressed by the spring |5 against the valve 2 of the gaspressure controller A, whereby the supply of gas to the burner C is shut off. when water is drawn off, a drop in pressure occurs at the contracted part l2, which results in a decrease of the pressure in the chamber 3 relative to the a pressure in the chamber I. The diaphragm is at the same time moved against the force of the spring l5, and the rod 4 permits the valve 2 to open in proportion to the quantity of water flowing through the pipes l3 and I4. Within the clearance for movement now available, the valve 2 can move to correspond to the conditions of gas pressure in such a way that the gas supply suitable for the heater cannot be exceeded even with a great gas pressure.

In the example of construction shown in Figure 2, the double seated valve 2, 2'0! a gas quantity controller A whose diaphragm is controlled by the drop in pressure occurring at a contracted part IT in the pipe I! leading to the burner C, is in communication by a two-armed lever l9, I! with a piston 25.

The piston is mounted with play in a casing 2| which is built into the cold water pipe I3, i4. The clearance between the piston and the wall of the casing takes the place of the constriction i2 in Fig. l. The drop in pressure occurring here tends to raise the piston in proportion to the quantity of water flowing through the pipe l3, H. The relief in weight occurring in ibis case effects an increased opening of the gas supply valve 2, 2' in proportion to the quantity of the water flowing through the heater D.

In the construction illustrated in Figure 3, an auxiliary gas pipe 2|, 2| branches off from the main gas pipe and at its endan ignition or pilot valve 22 of known kind is provided. The variations in pressure in the auxiliary pipe caused by this valve act in known manner on the diaphragm of the gas pressure control device A in such a way that the valve 2 can be opened only when the pilot flame is burning. In the appliance D which may be a boiler or supply container located in front of the burner C a thermostat 24 is arranged, the heat-sensitive member 25 of which can move the valve towards its seat when the temperature of the container requires a diminution of the gas supply. Within the clearance for movement 01 the valve allowed by the heat-sensl-' tive member 25 the valve 2 can perform control movements under the influence of the variations in pressure in the auxiliary pipe 2|.

The control arrangement shown in Figure 4 simply diflers from the constructions shown in amaavs Figures 1 to 3 by the controlling device B being provided with a valve 5 which governs the controlling cross section 25 at which the diflerences in pressure occur that are necessary for controlling the control device A formed as a gas quantity regulator. The effect of this arrangement is that the quantity of gas flowing to the burner C is solely dependent on the quantity of the water flowing to the heater D.

In the controlling arrangement shown in Figure 5, the valve 5 of the operating device B influenced by the flow of the medium to be heated is provided with a valve-like controlling piston 29 moving in a passage opening 28. The valve device A is operated by pressure variations which are controlled in an auxiliary gas passage on the one hand by a pilot valve 22, and on the other hand by a floating controller 34. The part 3| of the auxiliary gas passage is connected to a point in the main gas path which in the position of repose of the valve 5 is cut off from the gas supply. The valve 2 is thus held constantly closed under the influence of the spring 4| on the closure of the valve 5 even when the control valves 22 and 34 are opened. The valve 2 therefore can not seize even it the pilot valve 22 only seldom comes into operation. This arrangement of the auxiliary gas passage also gives the ad-- vantage that even when the passage crosssection is only slightly opened by the valve 5 an auxiliary gas current controlled by the valve 34 undertakes the control of the valve 2. An opening 28, serving as controlling cross section for the gas quantity to be supplied to the burner C, is arranged in a rotatable valve 35 adjustable from the outside. Said opening 28 can be more or less covered by a further rotatable valve 35 provided with an opening. This valve 36 is in communication with the gas cock 31 in'such a way that the free cross section 01 the opening 23, and thus the controlling movement of the valve 2,

is dependent on the position of this gas cock at each desired position of the valve 5 and the piston valve 29. A stop 40 secured to a ring 33 and adapted to be fastened by a set-screw 33 to the casing 01' the operating device B permits the degree of the mutual influencing of the two valves 5 and 2 to be limited to the extent desirable for the heater.

The operation of thedevice shown in Fig. 5 is as follows: When no waterv is flowing through the pipe l3, l4, the controlling valve 5 remains closed. As the auxiliary gas pressure is derived from the main gas flow behind the valve 5, no control-gas can flow through the passage 3| and over the floating controller 34 to the chambers 55 and 5| of the regulating device A and to the pilot burner E. The same pressure now prevails on both sides of the diaphragm I and therefore the force of the closing spring ean press the valve body 2 on to its seat. The pilot flame is extin'guished and therefore the thermostatic disc 52 of the pilot burner closes the pilot pipe 2|. To prevent the extinguishing of the pilot flame, a [small quantity ,of gas may flow continuously through a pipe 53. when the controlling valve 5 is opened by the pressure of the flowing water, gas flows through the passage 3|, over the floating controller 34 and through the passage 2| into the chamber 50; one part of the control gas flows through a throttle 54 into the chamber 5|. From the chamber 5| the gas can flow into the pilot line 2| and further to the pilot burner E. The pressure in the chamber 5| is therefore lower than the pressure in the chamber 55. The presc I 2,128,378 sure in the chamber 50 now presses thediaphragm is large, the openings 28 are fiuther opened.

This adjustment corresponds, however, only for a given pressure of the gas main. In order, even where the pressure in the mains is'variable, to enable auniform quantity of gas to be constantly supplied to the burner B, the valve 2 must narrow the gas passage when the mains pressure is higher and enlarge it when the mains pressure is smaller. The floating device 34 is employed for this p pose. A changing of the pressure in the main gas line influences the floating device 34 and thus the current of control gas which flows through the throttle 54 and the passage 2 I. .The floating device 34 is influenced by the diiference of the pressures which is producedby the openings 28. On the lower side of the disc acts the unthrottled pressure in the main gas line and on the upper side the reduced pressure behind the openings 28. If the main pressure increases, the floating device 34 throttles the control gas line. Therefore the pressure in the chamber 50 is reduced; consequently the valve 2 under the influence of the spring ll can now execute a closing movement. If'the pressure difference between the main gas line and the space behind the openings 28 is reduced to a value equal to or less than the weight of the disc 34, the disc is brought into its normal position. The throttling action thus ceases and the pressure. in the control chamber 50 above the diaphragm again increases, so that the control valve 2 is corre spondingly further opened. The varying pressure inthe mains is thus regulated by the floating device 34 automatically for the passage of a constant quantity.

We declare that what we claim is:

1. A controller for-gas-heated apparatus, including a'casing having a gas passage therein, a diiferential pressure operated gas valve insaid passage subject to variations in gas pressure and adapted to govern one condition in the gas flow, and an auxiliary valve in said gas passage sub- "ject to the influence of at least one factor in the working of the apparatus and adapted to cause gas pressure variations on opposite sides or saidvalve in accordance with variations in said factor and thus to cause variations in the adjustment of said gas valve on variation of said factor.

2. A controllerfc gas-heated apparatus, including a casing having a gas passage therein, a diflerential pressure operated regulator in said gas passage adapted to govern one condition in the gas flow, an adjustable t ottle member in the gas passage adapted to p uce difl'erential gas pressures on opposite sides of said regulator and-an adjusting member subject to the influence of at least'one'factor in the paratus adapted to adjust said throttle member.

3. A controller for gas-heated apparatus, including a casing having a gas passage therein, a difierential pressure operated regulator in said gas passage adapted to govern one condition in the gas flow, an adjustable throttle member in working of the 'apthe gas passage adapted to produce diflferential gas pressures for application to opposite sides of said regulator, an adjusting member subject to the influence of at least one factor in the working of the apparatus adapted to adjust said throttle member, and a valve control member subject to the influence of at least one factor in the working of the apparatus adapted to serve as shut-ofi valve and also as a control for the adjustment of said throttle member,

4. A controller for gas-heated apparatus, in-

cluding a casing having a gas passage therein, a

differential pressure operatbd regulator in said gas passage adapted to govern one condition in the gas flow, an adjustable throttle member in the gas passage adapted to produce differential gas pressures forapplicaticn to said regulator,

an adjusting member subjectto the influence of at least one factor in the working of the apparatus adapted to adjust said throttle member, and

-manually operable means for adjusting said throttle member.

5. A controller for gas-heated apparatus, including a casing having a gas passage therein, a differential pressure operated regulator in said gas passage adapted to govern one condition in the gas flow, an adjustable throttle member in the gas passage adapted to produce dilferential gas pressures for application to said regulator and an adjusting member subject to the influence of at least one factor in the working of the apparatus adapted to adjust said throttle member, and "manually operable means for adjusting the degre of influence of said adjusting member on said throttle member.

6. A controller for gas-heated apparatus, including a casing having a gas passage therein, a differential pressure operated regulator in said as passage adapted to govern one condition in t e gas-flow, an adjustable throttle member in the gas passageadapted to produce differential gas pressures for application to opposite sides of said regulator, an adjusting member subject to the influence of at least one factor in the working of the apparatus adapted to adjust said I throttle member and a gas cock adapted to gov- ,degree of influence of said adjusting member on said throttle member and a gas cook associated with'said manually operable member adapted. to govern the supply of gas to said casing, the association between said manually operable member and said gas-cock being such that the differential pressures produced by said throttle member are dependent upon the position of the as-cock. Y

8. A controller for gas-heated apparatus, including a casing having a gas passage'therein, a differential pressure operated regulator in said gas passage adapted to govern one condition in the gas flow, an adjustable throttle member in the gas passage adapted to produce diflerential gas pressures for application to said regulator, an adjusting member subjectto the influence of at least one'factor in the working of the-apparatus adapted to adjust said throttle member, manually operable means for adjusting the degree of influence of said adjusting member on said throttle member, and an adjustable stop for limiting the movement of said manually operable member.

9. A controller for gas-heated apparatus including a casing having a main gas passage and an auxiliary gas passage branching from said main gas passage, a gas valve governing the pressure of the gas flowing through said main gas passage and operable to normally maintain gas flow at a predetermined pressure through said main gas passage, said gas valve being subjected to variations in the gas pressure existing in said auxiliary gas passage, a control valve in said auxiliary gas passage and an adjusting member subject to the influence of at least one factor in the working of the apparatus adapted to adjust said control valve.

10. A controller for gas-heated apparatus including a casing having a main gas passage and an auxiliary gas passage branching therefrom, a gas valve in the main gas passage. and a gas regulator associated with said valve adapted to govern one condition in the gas flow through said main gas passage and subject to variations in pressure in said auxiliary gas passage, a valve member in the main gas passage serving also as control for the flow of gas into said auxiliary gas passage and an adjusting member for said valve member subject to the influence of at least one factor in the working of the apparatus.

11. A controller for gas-heated apparatus including a casing having a main gas passage and an auxiliary gas passage branching therefrom, a gas valve in the main gas passage and a gas regulator associated with said valve adapted to govern one condition in the gas flow through said main gas passage and subject to variations in pressure in said auxiliary gas passage, a valve member in the main gas passage serving also as control for the flow of gas into said auxiliary gas passage and an adjusting member for said, valve member subject to the influence of at least one factor in the working of the apparatus, said valve member being in advance of said gasvalve with regard to the direction of gas flow and said branch passage being located intermediate said valve member and said gas valve.

12. A controller for gas-heated. apparatus including a casing having a main gas passage and an auxiliary gas passage branching therefrom, a gas valve in the main gas passage and a gas regulator associated with said valve adapted to govern one condition in the gas flow through said main gas passage and subject to variations in pressure in said auxiliary gas passage, a valve member in said main gas passage in advance of said gas valve, having a part serving as a shut-- off valve and another part serving as a control for said auxiliary gas passage, said auxiliary gas passage branching from said main gas passage at a point between the portion of said valve member serving as a shut-off valve and the portion serving as a control for said auxiliary gas passage, and an adjusting member for said valve member subject to the influence of at least one factor in the working of the apparatus.

13. A controller for gas-heated apparatus including a casing having a main gas passage and an auxiliary gas passage branching therefrom, agasvalveinthemaingaspassageandagas regulator associated with said valveadapted to govern one condition in the gas flow through said main gas passage and subject to variations in pressure in said auxiliary gas passage, a valve member in said main gas passage in advance in said gas valve, having a part serving as a shutof! valve and another part serving as a control for said auxiliary gas passage, said auxiliary gas passage branching from said main gas passage, at a point between the portion of said valve member serving as a shut-off valve and the portion serving as a control for said auxiliary gas passage, an adjusting member for said valve member sub ject to the influence of at least one factor in the working of the apparatus, and a further auxiliary valve arranged in the auxiliary gas passage adapted to act upon said gas regulator and subject to a control by said adjusting member.

14. A controller for gas-heated apparatus comprising a main gas passage, a gas valve therein, a gas control device including an actuating member subject to differences in gas pressure on op posite sides thereof, and a supplementary control device in said main gas passage subject to a factor in the working of the apparatus and adapted to produce differential gas pressures for application to opposite sides of said actuating member to cause closure of said gas valve under a given condition of said factor, said control devices cooperating in such a manner that alterstions in the adjusting forces acting on the supplementary control device will cause an alteration in the loading on the other control device.

15. A controller for gas heated apparatus comprising a gas valve controlling a main gas passage, a gas pressure regulator including a diaphragm operated in accordance with gas pressure differences on opposite sides thereof associated with said valve and operable to regulate the pressure of the gas flowing through said valve, a governing device subject to one factor in the working of the apparatus, and an auxiliary gas valve in said main gas passage operable by said governing device, said governing device cooperating with said auxiliary gas valve to produce differential gas pressures for application to opposite sides of said regulator to cause closure of said pressure regulating gas valve under a given condition of said factor.

16. A controller for gas-heated apparatus, comprising a gas valve controlling a main gas passage,

a differential pressure operated regulator subject to variations of gas pressure on opposite sides thereof associated with said gas valve, 9. control device subject to the flow of a medium to be heated, and an auxiliary gas valve in said main gas passage operable by said control device, said control device cooperating with said auxiliary gas valve to produce diiferential gas pressures for application to opposite sides of said regulator to cause closure of said flrst mentioned gas valve on termination of the flow of said medium.

1'1. In a gas-heated apparatus, a gas burner, a main gas passage supplying gas to said burner, a gas valve in said main gas passage governing the flow to said burner, a pilot burner, means associated with said pilot burner and with said gas valve and adapted to close the gas valve when the flame of said pilot burner is extinguishe a control device subject to the flow of a medium to be heated, and an auxiliary gas valve in said main gas passage governing the flow of gas to said gas burner and operable by said control device, said control device cooperating with said auxiliary gas valve to cause closure of said firstmentioned gas valve, on termination. of-the flow of said medium.

18. A controllerfor gas-heated apparatus comprising a main gas passage, a gas valve theredition of said factor, said control devices coin, agas control device including a diaphragm operating in such a manner that alterations in subject to differences in gas pressure on opposite the adjusting forces acting on the supplementary sides thereof and adapted to control one condicontrol device will cause an alteration in the 5 tion in the gas flow, and a supplementary conloading on the other control device. 5

trol device in said main gas-passage subject to one factor in the working of the apparatus and GEORG HEGWEIN. adapted to produce differential gas pressures for OTTO MERTEN. application to opposite sides of said diaphragm to KURT FIEDLER. 10 cause closure of said gas valve under a given con- FRIEDRICH WILHELM STOCKMEYER. 10 

